To clarify on the above post title: iCloud calendar invites sometimes send calendar invites to Gmail users, but not always.

It appears that if the user's Gmail account is associated with an AppleID account, then that user will not receive an iCloud calendar event invitation email. I discovered this when I began looking into why my wife did not receive an invite at her Gmail account, which also happens to be her primary AppleID for iTunes/AppStore purchases.

I found that my own primary AppleID, also associated with a Gmail account, did not receive invites, either. However, a test Gmail account I have, that has never been associated with Apple/iTunes/iCloud/etc., receives invites just fine. Also, MS Exchange mailboxes receive the invites properly, as do Yahoo accounts.

Any ideas as to what the secret is here? I cannot believe Apple would decide to prevent invites being sent out to 3rd party addresses that happen to also be AppleIDs on their own system, as that'd be quite ludicrous.

Until now, there have been many, many Apple product users who've created AppleIDs associated with external email accounts, including Gmail. Now that iCloud has been released, many of them have turned on portions of iCloud or perhaps gone so far as to create iCloud email addresses/aliases under their primary AppleID.

Here's where it gets weird: there's a setting in iCloud calendar preferences turned on by default called "Use iCloud for incoming invitations". What this does is, if an invitation is sent to that primary AppleID (which is most often an external address) or its associated, newly-created iCloud address, it'll get routed to iCloud, preventing (blocking) the invite from being forwarded to that external address.

For example, a user's primary, pre-iCloud AppleID is john1234@gmail.com. iCloud is opened to the public, he enables it on an iDevice or Lion OS X and it asks if him to enter his AppleID credentials (john1234@gmail.com) and asks if he wants to create an iCloud address, which he does, john1234@me.com.

From now on, let's presume he's continuing to use his john1234@gmail.com account, because he's not really sure yet that he wants to make the switch to iCloud for email, etc. At this point, if another iCloud user sends him a calendar invite at his primary email, john1234@gmail.com, Apple has decided it'll route this invite directly to his john1234@me.com iCloud alias, never letting it send out to his Gmail account.

So, assuming he's not yet using iCloud email/alendar, he'll be clueless as to why he never received the invite OR, if he is using iCloud email/calendar alongside his primary Gmail account, he'll probably wonder how in the world an invite sent from a friend to his Gmail account is now showing up in his iCloud inbox/calendar.

Why Apple's enabled this by default is beyond me. At this point, it's preventing me from going to iCloud full-time because I can't be sure invitees will get my calendar events!

I'm having the exact same problem. I can send calendar invites fine to people that don't use gmail.

Yeah, it's bizarre. At first I thought it was some kind of clusterfrack related to Apple vs. Google, but when I discovered the strange behavior when sending to my own AppleID with associated iCloud address, I realized it's probably just that so many Gmail users are also iTunes users and, thus, use that address as their primary AppleID username.

Any update on this? I would love to use iCloud for my calendar but until there's a solution/workaround to this I will have to continue using my google calendar via an exchange account setup on my iPhone.

I've been fussing with this ever since I got my new Lion laptop with iCloud.

Invites will NOT be sent to anyone whose Apple ID is using their email address as the primary address. Mine won't send to my husband whose AppleID is a different email address, but his primary email address on the account is the one I am trying to send to for invites. It seems to work with other email addresses from any host as long as that address is not the primary email address for an Apple ID.

Oddly, I don't get the sending "whooosh" from Apple Mail that I used to get on my previous laptop, so it still doesn't SOUND like it's working, but it does actually send the email.

Apple won't let me log in right now (keeps insisting on creating an ID instead of just letting me login) so I can't check what they are saying about this.